Mobile communication devices may include a variety of components including circuit boards, integrated circuit (IC) devices and/or System-on-Chip (SoC) devices. The components may include processing devices, user interface components, storage and other peripheral components that communicate through a shared data communication bus, which may include a multi-drop serial bus or a parallel bus. General-purpose serial interfaces known in the industry include the Inter-Integrated Circuit (I2C or I2C) serial bus and its derivatives and alternatives. The Mobile Industry Processor Interface (MIPI) Alliance defines standards for I3C, the Radio Frequency Front-End (RFFE) interface and other interfaces.
In one example, the I3C serial bus may be used to connect sensors and other peripherals to a processor. In some implementations, multiple bus masters are coupled to the serial bus such that two or more devices can serve as bus master for different types of messages transmitted on the serial bus. In another example, the RFFE interface defines a communication interface for controlling various radio frequency (RF) front-end devices, including power amplifier (PA), low-noise amplifiers (LNAs), antenna tuners, filters, sensors, power management devices, switches, etc. These devices may be collocated in a single IC device or provided in multiple IC devices. In a mobile communications device, multiple antennas and radio transceivers may support multiple concurrent RF links In another example, system power management interface (SPMI) defined by the MIPI Alliance provides a hardware interface that may be implemented between baseband or application processors and peripheral components. In some implementations, the SPMI is deployed to support power management operations within a device.
In many instances, a multi-drop serial bus may be provided to support high-priority, low-latency communication between an application processor and certain peripherals, and other lower-priority communication. Latency can be adversely affected when multiple devices coupled to the serial bus are concurrently active and attempting to gain bus access for transmission initiation. Degraded latencies can lead to a failure to meet certain applications performance limits. As mobile communication devices continue to include a greater level of functionality, improved serial communication techniques are needed to improve latencies and/or handling of priority traffic on a serial bus that couples peripherals and application processors.